With rapid development of user equipment (UE) and mobile applications, mobile data traffic increases sharply, and it becomes increasingly difficult for an existing cellular network of a telecommunications operator to meet a data traffic growth requirement. Therefore, the telecommunications operator expects to bear apart of mobile data traffic by means of a wireless local area network (WLAN), so as to ease traffic load of the existing cellular network. To achieve this objective, the telecommunications operator not only needs to deploy an access point (AP) of a wireless local area network in advance for UE access, but also needs to determine whether the UE is located within coverage of the WLAN, that is, a WLAN discovery problem needs to be resolved.
At present, a corresponding WLAN module is usually enabled in a UE that supports WLAN access, so as to search for an available AP around the UE. However, if the UE is not located within coverage of the AP, continuous search consumes more power of the UE, and reduces usable time of the UE. In the prior art, a UE may discover a WLAN with assistance of a cellular network, for example, a WLAN discovery method based on a cellular cell identifier. When the UE enters a cellular cell for which an AP is deployed in advance, the cellular network can instruct the UE to start a WLAN access module to search for an available AP nearby, and then access the WLAN.
However, in the prior art, there is at least a technical disadvantage as follows: because coverage of a cellular cell is generally much wider than coverage of an AP, when a UE enters a cellular cell for which an AP is deployed, it may still not be determined whether the UE is located within the coverage of the AP. In this case, if the UE is instructed to start the WLAN access module, an available AP may still not be found, which degrades user experience and wastes UE power.